1956-1958 Lotus Eleven

In early 1956, when the Lotus Eleven was launched, it was an amazingly advanced design. Not only did it boast a rigid type of multi-tube chassis frame, but it featured an attractive wind-cheating body style.

Compared with any other racing sports car of the day, it was smaller, lighter, and better shaped than its rivals. It was proof, in the metal, of Chapman's philosophy, which was to push his new designs up to the very limits of known technology.

Chapman, who did all his own design work, was a daring and innovative engineer who made every bit of metal do its job to the utmost and who inspired the shaping of bodies to cheat the wind wherever possible. Then, as later, a Lotus was elegant if a touch fragile, beautiful and entirely functional, nimble and amazingly efficient.

Way back in the early 1950s, Colin Chapman was working rather unhappily as a civil engineer for the British Aluminum Company, Limited, but his passion was always for designing and building cars.
The "day job" was only there so that Colin could indulge himself to create special, lightweight sports cars.

Having built a short series of racing specials, called Lotus and based on the ubiquitous Austin Seven, there was a demand from British enthusiasts wanting be supplied with replicas.

This encouraged Chapman to set up a tiny business, which he could only attend to in the evenings. Using premises rented to him by the man whose daughter he would eventually marry, Chapman followed up with the first Lotus "production" car -- the open-wheeled Mark VI of 1953.

This rugged two-seater was built in tatty premises in Hornsey, North London, and sold in build-it-yourself kit form. Not only did this car put the Lotus name on the open market, it also introduced the term "space frame" to British buyers. From 1953-1962, almost every other Lotus would use the same type of construction.

After the Mark VI, which had all the aerodynamic qualities of a brick, Chapman then turned to the idea of an aerodynamic body form. One of his first part-time employees was Mike Costin, whose elder brother Frank was in charge of flight test aerodynamics at De Havilland Aircraft, so when the time came it was the elder Costin who was consulted.

Up to that time, Frank Costin had not appeared to be interested in cars, so he treated the challenge of clothing a modified Mark VI chassis purely as an aerodynamic exercise. When developing the Mark VIII, the result was that he didn't copy any existing style, but offered an attractive shape that was both efficient and unique.

Go on to the next page to learn about the development of the Lotus Eleven.

Development of the Lotus Eleven

The Mark VIII, which had appeared in 1954, also inspired the Mark X, which used larger engines, but its direct replacement was the smaller, and more delicate, Mark IX of 1955. But Chapman was still not satisfied, so he oversaw the development of the Lotus Eleven (the first Lotus whose number was always spelled out). It was launched in February 1956.

Here was a car that pushed Chapman's -- and Frank Costin's -- automotive knowledge to the limit. There were to be no compromises, even though the entrepreneurial Chapman wanted the new car to do several jobs for him. This was the first Lotus which was really a range of cars, rather than a single new model.

Chapman was not only looking for success, but for much increased sales; naturally he saw the Eleven as a racing sports car but, somewhat optimistically, he also expected to sell a few for road use.

Not only did Chapman want a winning sports car for his own purposes, but he wanted to finance his racing by selling lots of cars to customers. On the one hand, he wanted to sell the very best and very fastest possible car in the sports car classes; on the other, he wanted to attract Britain's clubmen with cheaper and simpler types.

There had been Lotuses with a choice of engines before, but this was to be the first Lotus with a choice of engines, body styles, and rear suspensions!

When Lotus' rivals saw the new Eleven, they were aghast, for this was a real advance on anything that had previously been sold from Hornsey. It was very easy for them to become depressed, for to produce a better car than this they had a mountain to climb.

Compared to any previous Lotus, and certainly against any rival product, the Eleven was smaller, lighter, more wickedly attractive, and more effective. The cynics -- pundits and motoring writers alike -- could only clutch at straws. Surely, they muttered, such a car would have to be fragile. Surely such a car would be unreliable. Surely the air intake was too small and the car's engine would overheat.

They were at once right -- and wrong. For the next few years, Lotus would gain a well-deserved reputation for building cars that suffered from component breakages, but in the face of criticism Colin Chapman maintained an Olympian calm.

There was nothing wrong with the design of his cars, he insisted -- breakages only occurred if the cars were badly maintained or roughly driven. For those whose cars suffered from chassis frames with fractured weld joints, or from brackets that cracked at a relatively early stage, this was no consolation.

Go on to the next page to learn about the production of the 1956-1958 Lotus Eleven.

Production of the 1956, 1957, 1958 Lotus Eleven

Now let's consider the production of the 1956, 1957, 1958 Lotus Eleven. The Lotus Eleven was a tiny, front-engined sports car with two seats, and the very minimal level of weather protection Chapman figured drivers would accept. The chassis was a space frame lightly clad with a sensuously detailed body built of ultra-thin aluminum panels.

Multi-tube space frames had originally been developed as the basic structure for military aircraft, with the principle gradually being adopted for use in postwar racing cars.

Although most people assume that the original automotive space frame had been designed by Mercedes-Benz (for the 300SL of 1952), one shouldn't forget the complex tubular frame utilized by Jaguar for the 1951 C-Type.

For use in Lotus sports cars, Chapman took the principle even further. Early Lotus space frames were not as delicate as those found in the 300SL, but the Eleven's frame was a delicate, even flimsy-looking, masterpiece.

As was already well-known, the correct way to design a true space frame was to link stress points by straight tubes that were only ever in tension or compression; incorrectly located tubes were subject to bending loads, which they could not easily withstand.

As far as motor cars were concerned, the need to get passengers in and out of the cockpit, and to allow for engine removal, meant that the Eleven's frame wasn't an ideal design. Within limits, however, Chapman and the Costin brothers had worked ruthlessly to provide an immensely strong frame, even though it looked flimsy.

Most of the tubes were 1.0-inch or 0.75-inch round -- or square -- section pieces. Depending on the loads they had to carry, they were either of 18 -- or (even thinner) 20 -- gauge thickness.

Stripped of all its aluminum bodywork, the bare frame weighed a mere 56 pounds, and there was no difference between the de Dion or live rear axle type suspensions in terms of weight. To add to the rigidity in key areas, Lotus arranged to rivet some of the inner body panels to the chassis frame.

Although the chassis layout was fascinating enough, it was the body style, and the fine detailing, which had gone into it, that caused most discussion. Compared with the Mark IX, which it replaced, the Eleven was even lower and smaller, the height at the scuttle, immediately ahead of the windscreen, being an astonishingly low 27 inches.

Given the basic dimensions already settled upon -- including an 85-inch wheel-base and the use of a Coventry-Climax engine -- Costin then designed a pure aerodynamic shape for front and rear wheelarch fairings.

As a perfectionist whose sensibilities were irritated by lots of joints, flaps, and badly fitting contours, he was delighted to know that Lotus proposed to build the entire front and rear body sections in one piece, and to hinge them at the extreme ends of the chassis frame.

Feedback for the Lotus Eleven

Let's consider the experts' feedback for the Lotus Eleven. As we now know, the Lotus Eleven's final shape was by no means ideal, for the front and rear fenders had to be enlarged to allow for wheel and steering movements.

Around the cockpit of the definitive Le Mans type, however, the lines were beautifully detailed, for there was a plastic screen wrapped around the driver's head, blending beautifully into a raised headrest which extended to the extreme end of the tail.

Road & Track actually calculated the car's aerodynamic performance, concluding that it was amazingly efficient, and that it required only nine horsepower to push it along at 60 mph.

To those who suggest Jaguar had already achieved the same thing with its D-Type, the answer is that great minds think alike, for the Jag had also been shaped by an aircraft-industry aerodynamicist.

Racing enthusiasts who already knew about the Mark IX rushed to order the new Eleven, and it wasn't long before Lotus claimed to be building four cars every week. Chapman was a peerless self-publicist, and we now know that this figure was rarely achieved, but there is no doubt that the Eleven was an instant success.

It wasn't merely the looks, but the lightness and sheer agility that made it such a formidable little car. Even though the swing-axle front suspension used components from Ford of Great Britain's most humble small car, the Eleven had tenacious grip, while the Coventry-Climax engines ensured high performance.

Racing successes came at once, and for the next three seasons the Eleven was usually a favorite to win in any 1.1-liter or 1.5-liter sports car racing category Lotus entered three "works" cars for the 1956 Le Mans 24 Hours race, where special regulations meant they had to have widened cockpits (plus special chassis frames).

One of the 1.1-liter cars won its class that year, but there was even greater success in 1957, when new cars (with modified wrap-over, full-width windshields) proved so fast that the American crew of Mackay Fraser and Chamberlain finished ninth overall at an average speed of 99.08 mph.

Not only that, another car, fitted with a special 750-cc Coventry-Climax engine went round like a train for 24 hours, won its class, finished 14th averaging 90 mph -- and won the Index of Performance category.

Other Elevens took speed records at Monza, Italy (Stirling Moss being one of the drivers), and privately owned cars were successful in the U.S., Australia, and throughout Europe, though on rougher tracks (such as Sebring, Florida), they were never as rugged as the heavier Porsches.

Legacy of the Lotus Eleven

Now we'll consider the legacy of the Lotus Eleven. The Series II version of the Lotus Eleven followed in 1957, this having a double-wishbone (A-arm) front suspension instead of the swing-axle layout, and modified body lines allowing for wider wheels and tires. It was a better car, but not sensationally better -- and the opposition was beginning to catch up.

Road & Track was about the only American magazine to road test an Eleven, equipped in this case with the 83-bhp Coventry-Climax engine. "The Lotus Mark XI . . . is now officially called 'Eleven,'" the magazine noted in March 1957, "and this test report brings forth some of the most startling performance data ever published."

The reason for that comment was that with 4.22:1 gearing, R&T achieved a top speed of 132.06 miles per hour, and figured that with the optional 3.66:1 gearset top speed would have been more like 145 mph.

"Acceleration, naturally, is really fierce even at low speeds," said the magazine, and indeed 0-60 mph came up in nine seconds flat. This was possible because of the extremely low weight of the car, just 1360 pounds gross test weight (1000 pounds dry weight) and the exceptional aerodynamics.

Steering was unusually quick with just 1.75 turns lock-to-lock, and there was "practically no roll at all, in a corner, but the ride is not designed for a comfortable Sunday trip."

"The Lotus Eleven is not a dual-purpose sports car-it is designed to win in Class G," R&T pointed out, "and the price of $5,467 delivered in the U.S.A. strikes us as being quite reasonable. ... Even the lowest priced model may not put a Lotus in every garage but it would certainly make an interesting class if enough cars of this type are brought over."

Lotus's old records have survived, showing that 150 Series I Elevens and about 125 Series II types were produced; Graham Arnold in the Illustrated Lotus Buyer's Guide reports that 64 Elevens were sent to the U.S.

Like other Lotus cars of the day, however, the Eleven was soon overwhelmed by new models incorporating yet other new Colin Chapman ideas. The Eleven's immediate successor, launched in 1958, was the Fifteen, and a year later this too was replaced, by the Seventeen.

That, you might think, was that -- but the Elevens came back into their own in historic racing categories in the USA and in Great Britain. Lotus was no longer interested in providing parts for the cars, so this had to be done privately. The demand for chassis and body items soon meant that remanufacture began -- and this is where the boom in Lotus Eleven replicas came from.

Go on to the next page to learn about 1956, 1957, and 1958 Lotus Eleven specifications.